Since we were the last distributor of Zeiss and Voigtlander lenses as Zeiss Ikon Voigtlander USA (up to 1979) I can tell you that both Rodenstock and Schneider were very strong in the US market well before we stopped offering the Zeiss and Voigtlander lenses. Zeiss lost their headway it seems when they lost major market share VS Leica and Nikon in the 35mm market. Voigtlander bounced around after their name was sold in the 70's Rollei and currently to the Ring Photo camera store group.
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